Unit 2- Lecture 2 AP II Flashcards
Which of the following axons can conduct AP the fastest?
A. 4 um, myelinated
B. 4 um, unmyelinated
C. 8 um, myelinated
D. 8 um, unmyelinated
C.
Conduction of APs
_________ AP conduction can only be seen experimentally
ability of AP to travel in ______ directions
Bidirectional
both
Conduction of APs
___________ conduction of AP is seen physiologically
*known as the standard or normal
Unilateral
Conduction of APs
When _________ APs occur along a single axon = signifies a __________ intensity of the signal
Multiple
higher
AP Conduction Facilitators:
Myelin Sheath main functions:
Made of _______ and provides ________ of nerve cells
Lipids
Insulation
AP Conduction Facilitators:
______ of _______ works together with the myelin sheath in between the ______ to allow flow in and out of the ______ which produces an ________ signal
Node, Ranvier
gaps
neuron
electrical
AP Conduction Facilitators:
Node of Ranvier has a __________- gated __________ channel, raises membrane voltage to create an ____
Voltage
sodium
AP
AP Conduction Facilitators: Myelin Sheath
___________ _____ in the nodes
____________ conduction: jumping among nodes
Regeneration AP
Salitory
AP Conduction Facilitators: Axon Size
Thicker = ________
Squid Giant Axon: ______-______ um diameter
_______-________ folds of 1 myelinated vertebrae axon
Faster
200, 800
100, 400
Myelin Sheath in the CNS & Pathology:
______________
________ axons
__________ axons by ___________
Oligodendrocytes
Multiple
Nonymyelinated
astrocytes
Myelin Sheath in the CNS & Pathology:
Which neurological condition affects the CNS?
Causes sporadic lesions and has varied S&S
Compromises CN ___ ?
Multiple Sclerosis
II
Myelin Sheath in PNS and pathology:
Affects _______ cells
______ axon of the myelin sheath
___________ axons by a single ________ cell
Schwann
Single
Nonmyelinated, Schwann
Myelin Sheath in PNS and pathology:
Which condition affects the PNS?
All ___________ axons in the PNS compromised
General _______ _________
Guillain Barre Syndrome
Myelinated
functional loss
Communicating Unit: Electric Synapse
___________ of cells
Has ______ junctions
AP __________ conduction
Connection
gap
bidirectional
Communicating Unit: Chemical Synapse
_____________ ________ _________: vesicles with neurotransmitters become released
Postsynaptic membrane: __________
Involves the synaptic ______ and _________
Presynaptic axon terminal
receptors
cleft
vesicle
___________ potential: stimulants on the receptive area
Receptor
___________ potential: induced through synapses
Synaptic
Intensity is represented by _________ below _________
amplitude
threshold
Action potential: above the _________, intensity is represented by _________
threshold
frequency
Transformation of Electrochemical signals? 1-6 stages
- Arrival of AP
- Open of voltage-gated Ca2+ channel
- Docking and fusion of vesicles
- Release of neurotransmitters
- Diffusion of neurotransmitters
- Binding ligand-gated ion channels
Electromechanical Transformation
_______ vesicles: diff. neurotransmitters
_________ presynaptic AP
small
single
Electromechanical Transformation
___________ receptors have what ion channels?
Ionotropic
Ligand-gated
Electromechanical Transformation
___________ receptors are fast: point-to-point, specific
Either depolarization: ?
or hyperpolarization: ?
Ionotropic
EPSP
IPSP
Electrochemical Transformation
_____________ receptors: GPCR, 2nd messenger system, slow
Either depolarization: ?
or hyperpolarization: ?
Metabotropic
EPSP
IPSP
Electrochemical Transformation
__________ presnyaptic AP
Large vesicles: neurotransmitters through _________
Small vesicles: neurotransmitters to _______ _________
Multiple
exocytosis
synaptic gap
Summation of Synaptic Potenial:
____________ summation: E1, timeframe
___________ summation: E1/E2, locations
temporal
spatial
Depolarization: between _____ _______ and _________
____________: below the threshold
rest potential
threshold
Hyperpolarization
Neuromuscular Junction (NMJ)
Presynaptic Membrane: LMN _____ _______
Synaptic _______
_________ shape synapses
Postsynaptic membrane: _________ membrane
axon terminal
cleft
button
muscle
The conduction speed of APs is dependent on which factors?
myelination
axon diameter
NMJ involves what neurotransmitter: ?
Acetylcholine
NMJ
Nicotinic Receptor is a _______-_______ Na+ channel, EPSP
ligand
gated
NMJ Presynaptic Channelopathies
Blocked _______ channel weakness results in __________
Ca 2+
flaccidity
NMJ Presynapric Channelopathies
Blocked _____ channel: impaired ___________
Continuosly release acetylcholine: ________
K+
repolarization
spasm
Lambert-Eaton syndrome is from a blocked ______ channel
Ca2+
Isaac’s syndrome: blocked ______ channel
K+
NMJ Postsnypatic Channelopathies:
The most common NMJ pathology ?
weakness, eye muscle the worst
What is a common condition associated with NMJ postsynaptic channelopathies?
Myasthenia Gravis
Myasthenia Gravis reults from which blocked neurotransmitter? and compromises what?
AChR
AChR localization
Fate of Neurotransmitter 4 stages?
Reuptake
Degradation
Diffusion Away
Endocytosis
Neurotransmitter Synthesis and Transportation:
Peptide Neurotransmitter
Peptide/enzymes from the _________
Transported to the _________
___________ to form _______ neurotransmitter
nucleus
terminals
digest, active
Neurotransmitter Synthesis and Transportation
Small Molecular Neurotransmitter
Enzymes synthesized in the ________
Transport to the _________
Synthesizing __________ in the terminals
soma
terminals
neurotransmitters
Pharamaceuticals Targeting Neurotransmitters
_________ activity
increase neurotransmitter release
agonists
disinhibition
prevent reuptake
block degradation
Increase
Which types of summation are available for a neuron to integrate all the receptor or synaptic potentials?
temporal
spatial
Pharamaceuticals Targeting Neurotransmitters
____________ activity
decrease neurotransmitter release
antagonist
decrease
